Abstract: We propose to conduct the Chandra Multiwavelength Plane (ChaMPlane) Survey to identify a large sample of serendipitous x-ray sources located to arcsec precision in the deep (\gsim30 ksec) galactic fields (b \lsim10\deg) imaged by the Chandra X-ray Observatory. Our primary goal is to identify cataclysmic variables (CVs) and quiescent Low Mass X-ray Binaries (qLMXBs), primarily black hole x-ray novae in quiescence, in order to constrain and ultimately measure the luminosity functions of each. Secondary objectives are to determine the Be x-ray binary content and stellar coronal source distributions in the Galaxy. The deep Chandra galactic fields will detect 2-6 keV fluxes (allowing for low energy absorption) of \Fx(2-6 keV)=2 \X 10^-15 erg/s and thus CVs or qLMXBs with \Lx=10^31 erg/s out to ~7 kpc. Thus most CVs and qLMXBs in the Galaxy can be reached, and the ChaMPlane survey offers the best chance for constraining their formation/evolution and the stellar BH content of the Galaxy. CVs and qLMXBs will be identified by their ubiquitous \Halpha excess as ``blue'' objects in the R vs. (\Halpha - R) plane down to R \about 24. We have demonstrated this technique for crowded fields with our HST discovery of the first CVs in globular cluster cores and have now conducted a successful pilot ChaMPlane survey at CTIO.